Hook up test runner to new layout_test_html_viewer

components/html_viewer/content_handler_impl.h

Index: components/html_viewer/content_handler_impl.h
diff --git a/components/html_viewer/content_handler_impl.h b/components/html_viewer/content_handler_impl.h
index 2258c8dfc803ea8dc21e49549602c6ea71270d26..2edbf5ead85ba3738ab394b47c22f73f0135e676 100644
--- a/components/html_viewer/content_handler_impl.h
+++ b/components/html_viewer/content_handler_impl.h
@@ -21,6 +21,10 @@ class ContentHandlerImpl : public mojo::ContentHandler {
                      mojo::InterfaceRequest<ContentHandler> request);
   ~ContentHandlerImpl() override;
 
+ protected:
+  GlobalState* global_state() const { return global_state_; }
+  mojo::ApplicationImpl* app() const { return app_; }
+
  private:
   // Overridden from ContentHandler:
   void StartApplication(mojo::InterfaceRequest<mojo::Application> request,